Since 2011, I’ve been attempting to farm San Marzano type tomatoes in my garden.The Italian sales pitch convinces me every year that the San Marzano tomatoes are the real and best sauce tomato. However, every year they get trumped by regular Romas in flavor, robustness, and yield. In our area and soil, the SM are very susceptible to blossom end rot. In the same conditions (even in the same raised bed), Romas exhibit no signs of BER. The SM produce about 25% of the volume of the Romas. The flavor of each type is really similar, and if you got the best specimen from each tomato type each harvest, it would be a tie.
Maybe you’ve had success with your San Marzanos and can share your tips with me. Until then, the Roma will stand as my go-to sauce tomato.